EN
Thermodynamic description is presented for the ternary Cu-Ni-Pb system. Optimized parameters of the sub-systems, Cu-Ni, Cu-Pb and Ni-Pb, are taken from earlier assessments and those of the ternary system are optimized in this study by using the experimental phase equilibrium and thermodynamic data. Better agreement is obtained by the present optimization. Calculated results are compared with the original experimental data to demonstrate the successfulness of this assessment. Moreover, a geometric model (general solution model) is used to estimate ternary integral molar Gibbs excess energies of the liquid phase from the bibary systems only. These values, however, disagree with the quantities obtained by thermodynamic optimizations. [...]